Background: The aim of this study was to examine the relationship between perfectionism and mental health according to the mediating role of organization self-esteem (OSE) in the official staff of the Iranian Oil Pipeline of the central region and Telecommunication Company of the southeast region, Rafsanjan, Iran.Materials and Methods: This descriptive research is a path way analysis. The statistical population included all employees at the Iranian Oil Pipeline and Telecommunication Company. Based on the Guernsey and Morgan tables, 95 subjects were selected as the samples through random method. In order to collect data, we employed three sets of questionnaires (perfectionism, mental health, and OSE) that have a proper validity and reliability. The data were analyzed using SPSS and PLS.Results: The significant coefficient of the route between OSE and mental health was 0.264 that was estimated less than 1.96. Thus, it can be reported that ther was not a significant association between OSE and mental health which means OSE did not affect mental health. Therefore, it can be said that perfectionism did not affect mental health with OSE as the mediator variable.Conclusions: According to the importance of using the skill of perfectionism, it can be used in increasing mental health in the organization.